Last stage safe flow monitoring and control system and method

Abstract

The invention belongs to the technical field of turbines, and particularly relates to a last stage safe flow monitoring and control system and method for a turbine. The last stage safe flow monitoringand control system comprises a last stage safe flow monitoring and control device connected with a turbine low pressure cylinder. The last stage safe flow monitoring and control device is used for collecting the exhaust steam pressure value of the turbine low pressure cylinder, and the allowed value range of the low pressure cylinder inlet steam parameter and / or the allowed value range of the lowpressure cylinder exhaust steam parameter are / is set according to the pressure value and compared with the actual measured value of the low pressure cylinder inlet steam parameter and / or the actual measured value of the low pressure cylinder exhaust steam parameter. When the actual measured values exceed the allowed value ranges, the steam inlet amount of the turbine low pressure cylinder is adjusted so that the actual measured values can be within the allowed value ranges. Monitoring and adjustment control of the last stage minimum safe flow of the large turbine are effectively achieved, safe and economic operation of a unit can be guaranteed, and the system has the characteristics of being simple in structure, safe and reliable.

Description

technical field [0001] The invention belongs to the technical field of steam turbines, in particular to a system and method for monitoring and controlling the safety flow of the final stage of a steam turbine. Background technique [0002] Steam turbine is the main driving equipment of large rotary equipment, especially generators, and it is widely used in modern industry, especially in the field of power generation. With the increase of unit capacity of power generation equipment, the length of the final stage blade of the steam turbine gradually increases, and the longer final stage blade will induce flutter under the small volume flow rate, and eventually lead to fatigue fracture of the blade, which seriously threatens the safe operation of large steam turbines. [0003] Usually steam turbine manufacturers stipulate a minimum safe volumetric flow rate during the design process of long blades, and take measures to ensure that the actual flow rate of the final stage of the ...

AI Technical Summary

Problems solved by technology

In order to improve energy utilization efficiency and heating economy, realize energy saving, water saving and harmful gas emission reduction, the waste heat utilization of heating units has been developed rapidly in recent years, but limited by the water flow and return water parameters of the heating network, the current double back Compressed double-rotor technology, low-pressure cylinder optical shaft technology, and absorption heat pump technology can only recover the waste heat of one unit. How to minimize the waste heat of the steam turbine and improve the power supply of the unit while ensuring the safety of the final blade Heat capacity and energy utilization efficiency are technical problems that need to be solved in the combined heat and power industry

[0005] In addition, under the renewable energy grid priority policy, in order to realize the thermoelectric decoupling of heating units, some enterprises have explored the possibility of cutting off the operation of the low-pressure cylinder, but limited by the minimum safe flow rate of the final stage, it has not yet been able to operate on a large scale for a long time

Images